static void _start_process(int err, seL4_Word pc, void *cookie) {
process_create_data *data = (process_create_data *) cookie;
if (err) {
_fail(err, data);
return;
}
seL4_UserContext context;
dprintf(5, "\tAttaching stdout and stderr...\n");
err = _create_stderrout(data->pcb);
if (err) {
_fail(err, data);
return;
}
dprintf(5, "\tSetting initial program counter...\n");
// Set initial seL4 thread context, starting the process
memset(&context, 0, sizeof(context));
context.pc = pc;
context.sp = SOS_PROCESS_STACK_TOP;
seL4_TCB_WriteRegisters(data->pcb->tcb_cap, 1, 0, 2, &context);
data->pcb->running = 1;
// Call back
_reply(SOS_PROCESS_SUCCESS, data->pcb->pid, data->cb, data->cookie);
_num_procs++;
free(data);
return;
}
int /*? me.interface.name ?*/__run(void) {
// Make connection to gdb
seL4_Word delegate_tcb;
seL4_UserContext regs;
while (1) {
seL4_Recv(/*? mem_ep ?*/, &delegate_tcb);
seL4_TCB_ReadRegisters(delegate_tcb, false, 0,
sizeof(seL4_UserContext) / sizeof(seL4_Word),
®s);
// Check eax is 0 so that we know they were checking memory
// TODO Add a check on pc to see if they were in the mem check function
if (regs.eax == 0) {
// Signal to the delegate the memory is invalid
regs.eax = 1;
// Increment past the faulting instruction
regs.eip += 2;
// Write registers back
seL4_TCB_WriteRegisters(delegate_tcb, false, 0,
sizeof(seL4_UserContext) / sizeof(seL4_Word),
®s);
// Resume the caller
seL4_MessageInfo_t info = seL4_MessageInfo_new(0, 0, 0, 1);
seL4_SetMR(0, regs.eip);
seL4_Reply(info);
}
}
}
int
are_tcbs_distinct(seL4_CPtr tcb1, seL4_CPtr tcb2)
{
int error, i;
seL4_UserContext regs;
/* Initialise regs to prevent compiler warning. */
error = seL4_TCB_ReadRegisters(tcb1, 0, 0, 1, ®s);
if (error) {
return error;
}
for (i = 0; i < 2; ++i) {
sel4utils_set_instruction_pointer(®s, i);
error = seL4_TCB_WriteRegisters(tcb1, 0, 0, 1, ®s);
/* Check that we had permission to do that and the cap was a TCB. */
if (error) {
return error;
}
error = seL4_TCB_ReadRegisters(tcb2, 0, 0, 1, ®s);
/* Check that we had permission to do that and the cap was a TCB. */
if (error) {
return error;
} else if (sel4utils_get_instruction_pointer(regs) != i) {
return 1;
}
}
return 0;
}
int
vm_set_bootargs(vm_t* vm, void* pc, uint32_t mach_type, uint32_t atags)
{
seL4_UserContext regs;
seL4_CPtr tcb;
int err;
assert(vm);
/* Write CPU registers */
tcb = vm_get_tcb(vm);
err = seL4_TCB_ReadRegisters(tcb, false, 0, sizeof(regs) / sizeof(regs.pc), ®s);
assert(!err);
regs.r0 = 0;
regs.r1 = mach_type;
regs.r2 = atags;
regs.pc = (seL4_Word)pc;
regs.cpsr = MODE_SUPERVISOR;
err = seL4_TCB_WriteRegisters(tcb, false, 0, sizeof(regs) / sizeof(regs.pc), ®s);
assert(!err);
return err;
}
static int
handle_syscall(vm_t* vm, seL4_Word length)
{
seL4_Word syscall, ip;
seL4_UserContext regs;
seL4_CPtr tcb;
int err;
syscall = seL4_GetMR(EXCEPT_IPC_SYS_MR_SYSCALL),
ip = seL4_GetMR(EXCEPT_IPC_SYS_MR_PC);
tcb = vm_get_tcb(vm);
err = seL4_TCB_ReadRegisters(tcb, false, 0, sizeof(regs) / sizeof(regs.pc), ®s);
assert(!err);
regs.pc += 4;
DSTRACE("Syscall %d from [%s]\n", syscall, vm->name);
switch (syscall) {
case 65:
sys_pa_to_ipa(vm, ®s);
break;
case 66:
sys_ipa_to_pa(vm, ®s);
break;
case 67:
sys_nop(vm, ®s);
break;
default:
printf("%sBad syscall from [%s]: scno "DFMT" at PC: 0x"XFMT"%s\n",
CERROR, vm->name, syscall, ip, CNORMAL);
return -1;
}
err = seL4_TCB_WriteRegisters(tcb, false, 0, sizeof(regs) / sizeof(regs.pc), ®s);
assert(!err);
return 0;
}
int main(void)
{
int error;
/* give us a name: useful for debugging if the thread faults */
name_thread(seL4_CapInitThreadTCB, "hello-3");
/* get boot info */
info = seL4_GetBootInfo();
/* print out bootinfo */
print_bootinfo(info);
/* get our cspace root cnode */
seL4_CPtr cspace_cap;
cspace_cap = seL4_CapInitThreadCNode;
/* get our vspace root page directory */
seL4_CPtr pd_cap;
pd_cap = seL4_CapInitThreadPD;
/* TODO 1: Find free cap slots for the caps to the:
* - tcb
* - ipc frame
* - endpoint
* - badged endpoint
* - page table
* hint: The bootinfo struct contains a range of free cap slot indices.
*/
/* decide on slots to use based on what is free */
seL4_CPtr tcb_cap = ???;
seL4_CPtr ipc_frame_cap = ???;
ep_cap = ???;
badged_ep_cap = ???;
seL4_CPtr page_table_cap = ???;
/* get an untyped to retype into all the objects we will need */
seL4_CPtr untyped;
/* TODO 2: Obtain a cap to an untyped which is large enough to contain:
* - tcb
* - ipc frame
* - endpoint
* - badged endpoint
* - page table
*
* hint 1: determine the size of each object
* (look in libs/libsel4/arch_include/x86/sel4/arch/types.h)
* hint 2: an array of untyped caps, and a corresponding array of untyped sizes
* can be found in the bootinfo struct
* hint 3: a single untyped cap can be retyped multiple times. Each time, an appropriately sized chunk
* of the object is "chipped off". For simplicity, find a cap to an untyped which is large enough
* to contain all required objects.
*/
/* TODO 3: Using the untyped, create the required objects, storing their caps in the roottask's root cnode.
*
* hint 1: int seL4_Untyped_Retype(seL4_Untyped service, int type, int size_bits, seL4_CNode root, int node_index, int node_depth, int node_offset, int num_objects)
* hint 2: use a depth of 32
* hint 3: use cspace_cap for the root cnode AND the cnode_index
*/
/*
* map the frame into the vspace at ipc_buffer_vaddr.
* To do this we first try to map it in to the root page directory.
* If there is already a page table mapped in the appropriate slot in the
* page diretory where we can insert this frame, then this will succeed.
* Otherwise we first need to create a page table, and map it in to
* the page`directory, before we can map the frame in.
*/
seL4_Word ipc_buffer_vaddr;
ipc_buffer_vaddr = IPCBUF_VADDR;
error = seL4_IA32_Page_Map(ipc_frame_cap, pd_cap, ipc_buffer_vaddr,
seL4_AllRights, seL4_IA32_Default_VMAttributes);
if (error != 0) {
/* TODO 4: Retype the untyped into page table (if this was done in TODO 3, ignore this). */
error = seL4_IA32_PageTable_Map(page_table_cap, pd_cap,
ipc_buffer_vaddr, seL4_IA32_Default_VMAttributes);
assert(error == 0);
/* then map the frame in */
error = seL4_IA32_Page_Map(ipc_frame_cap, pd_cap,
ipc_buffer_vaddr, seL4_AllRights, seL4_IA32_Default_VMAttributes);
assert(error == 0);
}
/* set the IPC buffer's virtual address in a field of the IPC buffer */
seL4_IPCBuffer *ipcbuf = (seL4_IPCBuffer*)ipc_buffer_vaddr;
ipcbuf->userData = ipc_buffer_vaddr;
/* TODO 5: Mint a copy of the endpoint cap into our cspace, using the badge EP_BADGE
* hint: int seL4_CNode_Mint(seL4_CNode service, seL4_Word dest_index, seL4_Uint8 dest_depth, seL4_CNode src_root, seL4_Word src_index, seL4_Uint8 src_depth, seL4_CapRights rights, seL4_CapData_t badge);
*/
/* initialise the new TCB */
error = seL4_TCB_Configure(tcb_cap, seL4_CapNull, seL4_MaxPrio,
cspace_cap, seL4_NilData, pd_cap, seL4_NilData,
ipc_buffer_vaddr, ipc_frame_cap);
assert(error == 0);
/* give the new thread a name */
name_thread(tcb_cap, "hello-3: thread_2");
/* set start up registers for the new thread */
size_t regs_size = sizeof(seL4_UserContext) / sizeof(seL4_Word);
/* check that stack is aligned correctly */
uintptr_t thread_2_stack_top = (uintptr_t)thread_2_stack + sizeof(thread_2_stack);
assert(thread_2_stack_top % (sizeof(seL4_Word) * 2) == 0);
/* set instruction pointer, stack pointer and gs register (used for thread local storage) */
seL4_UserContext regs = {
.eip = (seL4_Word)thread_2,
.esp = (seL4_Word)thread_2_stack_top,
.gs = IPCBUF_GDT_SELECTOR
};
/* actually write the TCB registers. */
error = seL4_TCB_WriteRegisters(tcb_cap, 0, 0, regs_size, ®s);
assert(error == 0);
/* start the new thread running */
error = seL4_TCB_Resume(tcb_cap);
assert(error == 0);
/* we are done, say hello */
printf("main: hello world\n");
/*
* now send a message to the new thread, and wait for a reply
*/
seL4_Word msg;
seL4_MessageInfo_t tag;
/* set the data to send. We send it in the first message register */
tag = seL4_MessageInfo_new(0, 0, 0, 1);
seL4_SetMR(0, MSG_DATA);
/* send and wait for a reply */
tag = seL4_Call(badged_ep_cap, tag);
/* check that we got the expected repy */
assert(seL4_MessageInfo_get_length(tag) == 1);
msg = seL4_GetMR(0);
assert(msg == ~MSG_DATA);
printf("main: got a reply: %#x\n", msg);
return 0;
}
int main(void)
{
UNUSED int error;
/* Set up logging and give us a name: useful for debugging if the thread faults */
zf_log_set_tag_prefix("hello-3:");
name_thread(seL4_CapInitThreadTCB, "hello-3");
/* get boot info */
info = seL4_GetBootInfo();
/* init simple */
simple_default_init_bootinfo(&simple, info);
/* print out bootinfo and other info about simple */
simple_print(&simple);
/* create an allocator */
allocman = bootstrap_use_current_simple(&simple, ALLOCATOR_STATIC_POOL_SIZE, allocator_mem_pool);
ZF_LOGF_IF(allocman == NULL, "Failed to initialize alloc manager.\n"
"\tMemory pool sufficiently sized?\n"
"\tMemory pool pointer valid?\n");
/* create a vka (interface for interacting with the underlying allocator) */
allocman_make_vka(&vka, allocman);
/* get our cspace root cnode */
seL4_CPtr cspace_cap;
cspace_cap = simple_get_cnode(&simple);
/* get our vspace root page directory */
seL4_CPtr pd_cap;
pd_cap = simple_get_pd(&simple);
/* create a new TCB */
vka_object_t tcb_object = {0};
error = vka_alloc_tcb(&vka, &tcb_object);
ZF_LOGF_IFERR(error, "Failed to allocate new TCB.\n"
"\tVKA given sufficient bootstrap memory?");
/*
* create and map an ipc buffer:
*/
/* TODO 1: get a frame cap for the ipc buffer */
/* hint: vka_alloc_frame()
* int vka_alloc_frame(vka_t *vka, uint32_t size_bits, vka_object_t *result)
* @param vka Pointer to vka interface.
* @param size_bits Frame size: 2^size_bits
* @param result Structure for the Frame object. This gets initialised.
* @return 0 on success
* Link to source: https://wiki.sel4.systems/seL4%20Tutorial%203#TODO_1:
*/
vka_object_t ipc_frame_object;
error = vka_alloc_frame(&vka, IPCBUF_FRAME_SIZE_BITS, &ipc_frame_object);
ZF_LOGF_IFERR(error, "Failed to alloc a frame for the IPC buffer.\n"
"\tThe frame size is not the number of bytes, but an exponent.\n"
"\tNB: This frame is not an immediately usable, virtually mapped page.\n")
/*
* map the frame into the vspace at ipc_buffer_vaddr.
* To do this we first try to map it in to the root page directory.
* If there is already a page table mapped in the appropriate slot in the
* page diretory where we can insert this frame, then this will succeed.
* Otherwise we first need to create a page table, and map it in to
* the page directory, before we can map the frame in. */
seL4_Word ipc_buffer_vaddr = IPCBUF_VADDR;
/* TODO 2: try to map the frame the first time */
/* hint 1: seL4_ARCH_Page_Map()
* The *ARCH* versions of seL4 sys calls are abstractions over the architecture provided by libsel4utils
* this one is defined as:
* #define seL4_ARCH_Page_Map seL4_X86_Page_Map
* in: Link to source: https://wiki.sel4.systems/seL4%20Tutorial%203#TODO_2:
* The signature for the underlying function is:
* int seL4_X86_Page_Map(seL4_X86_Page service, seL4_X86_PageDirectory pd, seL4_Word vaddr, seL4_CapRights rights, seL4_X86_VMAttributes attr)
* @param service Capability to the page to map.
* @param pd Capability to the VSpace which will contain the mapping.
* @param vaddr Virtual address to map the page into.
* @param rights Rights for the mapping.
* @param attr VM Attributes for the mapping.
* @return 0 on success.
*
* Note: this function is generated during build. It is generated from the following definition:
* Link to source: https://wiki.sel4.systems/seL4%20Tutorial%203#TODO_2:
* You can find out more about it in the API manual: http://sel4.systems/Info/Docs/seL4-manual-3.0.0.pdf
*
* hint 2: for the rights, use seL4_AllRights
* hint 3: for VM attributes use seL4_ARCH_Default_VMAttributes
* Hint 4: It is normal for this function call to fail. That means there are
* no page tables with free slots -- proceed to the next step where you'll
* be led to allocate a new empty page table and map it into the VSpace,
* before trying again.
*/
error = seL4_ARCH_Page_Map(ipc_frame_object.cptr, pd_cap, ipc_buffer_vaddr,
seL4_AllRights, seL4_ARCH_Default_VMAttributes);
if (error != 0) {
/* TODO 3: create a page table */
/* hint: vka_alloc_page_table()
* int vka_alloc_page_table(vka_t *vka, vka_object_t *result)
* @param vka Pointer to vka interface.
* @param result Structure for the PageTable object. This gets initialised.
* @return 0 on success
* Link to source: https://wiki.sel4.systems/seL4%20Tutorial%203#TODO_3:
*/
vka_object_t pt_object;
error = vka_alloc_page_table(&vka, &pt_object);
ZF_LOGF_IFERR(error, "Failed to allocate new page table.\n");
/* TODO 4: map the page table */
/* hint 1: seL4_ARCH_PageTable_Map()
* The *ARCH* versions of seL4 sys calls are abstractions over the architecture provided by libsel4utils
* this one is defined as:
* #define seL4_ARCH_PageTable_Map seL4_X86_PageTable_Map
* Link to source: https://wiki.sel4.systems/seL4%20Tutorial%203#TODO_4:
* The signature for the underlying function is:
* int seL4_X86_PageTable_Map(seL4_X86_PageTable service, seL4_X86_PageDirectory pd, seL4_Word vaddr, seL4_X86_VMAttributes attr)
* @param service Capability to the page table to map.
* @param pd Capability to the VSpace which will contain the mapping.
* @param vaddr Virtual address to map the page table into.
* @param rights Rights for the mapping.
* @param attr VM Attributes for the mapping.
* @return 0 on success.
*
* Note: this function is generated during build. It is generated from the following definition:
* Link to source: https://wiki.sel4.systems/seL4%20Tutorial%203#TODO_4:
* You can find out more about it in the API manual: http://sel4.systems/Info/Docs/seL4-manual-3.0.0.pdf
*
* hint 2: for VM attributes use seL4_ARCH_Default_VMAttributes
*/
error = seL4_ARCH_PageTable_Map(pt_object.cptr, pd_cap,
ipc_buffer_vaddr, seL4_ARCH_Default_VMAttributes);
ZF_LOGF_IFERR(error, "Failed to map page table into VSpace.\n"
"\tWe are inserting a new page table into the top-level table.\n"
"\tPass a capability to the new page table, and not for example, the IPC buffer frame vaddr.\n")
/* TODO 5: then map the frame in */
/* hint 1: use seL4_ARCH_Page_Map() as above
* hint 2: for the rights, use seL4_AllRights
* hint 3: for VM attributes use seL4_ARCH_Default_VMAttributes
*/
error = seL4_ARCH_Page_Map(ipc_frame_object.cptr, pd_cap,
ipc_buffer_vaddr, seL4_AllRights, seL4_ARCH_Default_VMAttributes);
ZF_LOGF_IFERR(error, "Failed again to map the IPC buffer frame into the VSpace.\n"
"\t(It's not supposed to fail.)\n"
"\tPass a capability to the IPC buffer's physical frame.\n"
"\tRevisit the first seL4_ARCH_Page_Map call above and double-check your arguments.\n");
}
/* set the IPC buffer's virtual address in a field of the IPC buffer */
seL4_IPCBuffer *ipcbuf = (seL4_IPCBuffer*)ipc_buffer_vaddr;
ipcbuf->userData = ipc_buffer_vaddr;
/* TODO 6: create an endpoint */
/* hint: vka_alloc_endpoint()
* int vka_alloc_endpoint(vka_t *vka, vka_object_t *result)
* @param vka Pointer to vka interface.
* @param result Structure for the Endpoint object. This gets initialised.
* @return 0 on success
* Link to source: https://wiki.sel4.systems/seL4%20Tutorial%203#TODO_6:
*/
error = vka_alloc_endpoint(&vka, &ep_object);
ZF_LOGF_IFERR(error, "Failed to allocate new endpoint object.\n");
/* TODO 7: make a badged copy of it in our cspace. This copy will be used to send
* an IPC message to the original cap */
/* hint 1: vka_mint_object()
* int vka_mint_object(vka_t *vka, vka_object_t *object, cspacepath_t *result, seL4_CapRights rights, seL4_CapData_t badge)
* @param[in] vka The allocator for the cspace.
* @param[in] object Target object for cap minting.
* @param[out] result Allocated cspacepath.
* @param[in] rights The rights for the minted cap.
* @param[in] badge The badge for the minted cap.
* @return 0 on success
*
* Link to source: https://wiki.sel4.systems/seL4%20Tutorial%203#TODO_7:
*
* hint 2: for the rights, use seL4_AllRights
* hint 3: for the badge use seL4_CapData_Badge_new()
* seL4_CapData_t CONST seL4_CapData_Badge_new(seL4_Uint32 Badge)
* @param[in] Badge The badge number to use
* @return A CapData structure containing the desired badge info
*
* seL4_CapData_t is generated during build.
* The type definition and generated field access functions are defined in a generated file:
* build/x86/pc99/libsel4/include/sel4/types_gen.h
* It is generated from the following definition:
* Link to source: https://wiki.sel4.systems/seL4%20Tutorial%203#TODO_7:
* You can find out more about it in the API manual: http://sel4.systems/Info/Docs/seL4-manual-3.0.0.pdf
*
* hint 4: for the badge use EP_BADGE
*/
error = vka_mint_object(&vka, &ep_object, &ep_cap_path, seL4_AllRights,
seL4_CapData_Badge_new(EP_BADGE));
ZF_LOGF_IFERR(error, "Failed to mint new badged copy of IPC endpoint.\n"
"\tseL4_Mint is the backend for vka_mint_object.\n"
"\tseL4_Mint is simply being used here to create a badged copy of the same IPC endpoint.\n"
"\tThink of a badge in this case as an IPC context cookie.\n");
/* initialise the new TCB */
error = seL4_TCB_Configure(tcb_object.cptr, seL4_CapNull, seL4_PrioProps_new(seL4_MaxPrio, seL4_MaxPrio),
cspace_cap, seL4_NilData, pd_cap, seL4_NilData,
ipc_buffer_vaddr, ipc_frame_object.cptr);
ZF_LOGF_IFERR(error, "Failed to configure the new TCB object.\n"
"\tWe're running the new thread with the root thread's CSpace.\n"
"\tWe're running the new thread in the root thread's VSpace.\n");
/* give the new thread a name */
name_thread(tcb_object.cptr, "hello-3: thread_2");
/* set start up registers for the new thread */
seL4_UserContext regs = {0};
size_t regs_size = sizeof(seL4_UserContext) / sizeof(seL4_Word);
/* set instruction pointer where the thread shoud start running */
sel4utils_set_instruction_pointer(®s, (seL4_Word)thread_2);
/* check that stack is aligned correctly */
const int stack_alignment_requirement = sizeof(seL4_Word) * 2;
uintptr_t thread_2_stack_top = (uintptr_t)thread_2_stack + sizeof(thread_2_stack);
ZF_LOGF_IF(thread_2_stack_top % (stack_alignment_requirement) != 0,
"Stack top isn't aligned correctly to a %dB boundary.\n"
"\tDouble check to ensure you're not trampling.",
stack_alignment_requirement);
/* set stack pointer for the new thread. remember the stack grows down */
sel4utils_set_stack_pointer(®s, thread_2_stack_top);
/* set the fs register for IPC buffer */
regs.fs = IPCBUF_GDT_SELECTOR;
/* actually write the TCB registers. */
error = seL4_TCB_WriteRegisters(tcb_object.cptr, 0, 0, regs_size, ®s);
ZF_LOGF_IFERR(error, "Failed to write the new thread's register set.\n"
"\tDid you write the correct number of registers? See arg4.\n");
/* start the new thread running */
error = seL4_TCB_Resume(tcb_object.cptr);
ZF_LOGF_IFERR(error, "Failed to start new thread.\n");
/* we are done, say hello */
printf("main: hello world\n");
/*
* now send a message to the new thread, and wait for a reply
*/
seL4_Word msg;
seL4_MessageInfo_t tag;
/* TODO 8: set the data to send. We send it in the first message register */
/* hint 1: seL4_MessageInfo_new()
* seL4_MessageInfo_t CONST seL4_MessageInfo_new(seL4_Uint32 label, seL4_Uint32 capsUnwrapped, seL4_Uint32 extraCaps, seL4_Uint32 length)
* @param label The value of the label field
* @param capsUnwrapped The value of the capsUnwrapped field
* @param extraCaps The value of the extraCaps field
* @param length The number of message registers to send
* @return The seL4_MessageInfo_t containing the given values.
*
* seL4_MessageInfo_new() is generated during build. It can be found in:
* build/x86/pc99/libsel4/include/sel4/types_gen.h
* It is generated from the following definition:
* Link to source: https://wiki.sel4.systems/seL4%20Tutorial%203#TODO_8:
*
* hint 2: use 0 for the first 3 fields.
* hint 3: send only 1 message register of data
*
* hint 4: seL4_SetMR()
* void seL4_SetMR(int i, seL4_Word mr)
* @param i The message register to write
* @param mr The value of the message register
* Link to source: https://wiki.sel4.systems/seL4%20Tutorial%203#TODO_8:
* You can find out more about message registers in the API manual: http://sel4.systems/Info/Docs/seL4-manual-3.0.0.pdf
*
* hint 5: send MSG_DATA
*/
tag = seL4_MessageInfo_new(0, 0, 0, 1);
seL4_SetMR(0, MSG_DATA);
/* TODO 9: send and wait for a reply. */
/* hint: seL4_Call()
* seL4_MessageInfo_t seL4_Call(seL4_CPtr dest, seL4_MessageInfo_t msgInfo)
* @param dest The capability to be invoked.
* @param msgInfo The messageinfo structure for the IPC. This specifies information about the message to send (such as the number of message registers to send).
* @return A seL4_MessageInfo_t structure. This is information about the repy message.
* Link to source: https://wiki.sel4.systems/seL4%20Tutorial%203#TODO_9:
* You can find out more about it in the API manual: http://sel4.systems/Info/Docs/seL4-manual-3.0.0.pdf
*
* hint 2: seL4_MessageInfo_t is generated during build.
* The type definition and generated field access functions are defined in a generated file:
* build/x86/pc99/libsel4/include/sel4/types_gen.h
* It is generated from the following definition:
* Link to source: https://wiki.sel4.systems/seL4%20Tutorial%203#TODO_9:
* You can find out more about it in the API manual: http://sel4.systems/Info/Docs/seL4-manual-3.0.0.pdf
*/
tag = seL4_Call(ep_cap_path.capPtr, tag);
/* TODO 10: get the reply message */
/* hint: seL4_GetMR()
* seL4_Word seL4_GetMR(int i)
* @param i The message register to retreive
* @return The message register value
* Link to source: https://wiki.sel4.systems/seL4%20Tutorial%203#TODO_10:
* You can find out more about message registers in the API manual: http://sel4.systems/Info/Docs/seL4-manual-3.0.0.pdf
*/
msg = seL4_GetMR(0);
/* check that we got the expected repy */
ZF_LOGF_IF(seL4_MessageInfo_get_length(tag) != 1,
"Response data from thread_2 was not the length expected.\n"
"\tHow many registers did you set with seL4_SetMR within thread_2?\n");
ZF_LOGF_IF(msg != ~MSG_DATA,
"Response data from thread_2's content was not what was expected.\n");
printf("main: got a reply: %#x\n", msg);
return 0;
}
int
vm_event(vm_t* vm, seL4_MessageInfo_t tag)
{
seL4_Word label;
seL4_Word length;
label = seL4_MessageInfo_get_label(tag);
length = seL4_MessageInfo_get_length(tag);
switch (label) {
case SEL4_PFIPC_LABEL: {
int err;
fault_t* fault;
fault = vm->fault;
err = new_fault(fault);
assert(!err);
do {
err = handle_page_fault(vm, fault);
if (err) {
return -1;
}
} while (!fault_handled(fault));
}
break;
case SEL4_EXCEPT_IPC_LABEL: {
int err;
assert(length == SEL4_EXCEPT_IPC_LENGTH);
err = handle_syscall(vm, length);
assert(!err);
if (!err) {
seL4_MessageInfo_t reply;
reply = seL4_MessageInfo_new(0, 0, 0, 0);
seL4_Reply(reply);
}
}
break;
case SEL4_USER_EXCEPTION_LABEL: {
seL4_Word ip;
int err;
assert(length == SEL4_USER_EXCEPTION_LENGTH);
ip = seL4_GetMR(0);
err = handle_exception(vm, ip);
assert(!err);
if (!err) {
seL4_MessageInfo_t reply;
reply = seL4_MessageInfo_new(0, 0, 0, 0);
seL4_Reply(reply);
}
}
break;
case SEL4_VGIC_MAINTENANCE_LABEL: {
int idx;
int err;
assert(length == SEL4_VGIC_MAINTENANCE_LENGTH);
idx = seL4_GetMR(EXCEPT_IPC_SYS_MR_R0);
/* Currently not handling spurious IRQs */
assert(idx >= 0);
err = handle_vgic_maintenance(vm, idx);
assert(!err);
if (!err) {
seL4_MessageInfo_t reply;
reply = seL4_MessageInfo_new(0, 0, 0, 0);
seL4_Reply(reply);
}
}
break;
case SEL4_VCPU_FAULT_LABEL: {
seL4_MessageInfo_t reply;
seL4_UserContext regs;
seL4_CPtr tcb;
uint32_t hsr;
int err;
assert(length == SEL4_VCPU_FAULT_LENGTH);
hsr = seL4_GetMR(EXCEPT_IPC_SYS_MR_R0);
/* Increment the PC and ignore the fault */
tcb = vm_get_tcb(vm);
err = seL4_TCB_ReadRegisters(tcb, false, 0,
sizeof(regs) / sizeof(regs.pc), ®s);
assert(!err);
switch (hsr) {
case HSR_WFI:
case HSR_WFE:
regs.pc += (regs.cpsr & BIT(5)) ? 2 : 4;
err = seL4_TCB_WriteRegisters(tcb, false, 0,
sizeof(regs) / sizeof(regs.pc), ®s);
assert(!err);
reply = seL4_MessageInfo_new(0, 0, 0, 0);
seL4_Reply(reply);
return 0;
default:
printf("Unhandled VCPU fault from [%s]: HSR 0x%08x\n", vm->name, hsr);
print_ctx_regs(®s);
return -1;
}
}
break;
default:
/* What? Why are we here? What just happened? */
printf("Unknown fault from [%s]: label=0x%x length=0x%x\n",
vm->name, label, length);
return -1;
}
return 0;
}
int main(void)
{
UNUSED int error;
/* give us a name: useful for debugging if the thread faults */
name_thread(seL4_CapInitThreadTCB, "hello-3");
/* get boot info */
info = seL4_GetBootInfo();
/* init simple */
simple_default_init_bootinfo(&simple, info);
/* print out bootinfo and other info about simple */
simple_print(&simple);
/* create an allocator */
allocman = bootstrap_use_current_simple(&simple, ALLOCATOR_STATIC_POOL_SIZE, allocator_mem_pool);
assert(allocman);
/* create a vka (interface for interacting with the underlying allocator) */
allocman_make_vka(&vka, allocman);
/* get our cspace root cnode */
seL4_CPtr cspace_cap;
cspace_cap = simple_get_cnode(&simple);
/* get our vspace root page directory */
seL4_CPtr pd_cap;
pd_cap = simple_get_pd(&simple);
/* create a new TCB */
vka_object_t tcb_object = {0};
error = vka_alloc_tcb(&vka, &tcb_object);
assert(error == 0);
/*
* create and map an ipc buffer:
*/
/* TODO 1: get a frame cap for the ipc buffer */
/* hint: vka_alloc_frame()
* int vka_alloc_frame(vka_t *vka, uint32_t size_bits, vka_object_t *result)
* @param vka Pointer to vka interface.
* @param size_bits Frame size: 2^size_bits
* @param result Structure for the Frame object. This gets initialised.
* @return 0 on success
* https://github.com/seL4/libsel4vka/blob/master/include/vka/object.h#L147
*/
vka_object_t ipc_frame_object;
error = vka_alloc_frame(&vka, IPCBUF_FRAME_SIZE_BITS, &ipc_frame_object);
assert(error == 0);
/*
* map the frame into the vspace at ipc_buffer_vaddr.
* To do this we first try to map it in to the root page directory.
* If there is already a page table mapped in the appropriate slot in the
* page diretory where we can insert this frame, then this will succeed.
* Otherwise we first need to create a page table, and map it in to
* the page directory, before we can map the frame in. */
seL4_Word ipc_buffer_vaddr = IPCBUF_VADDR;
/* TODO 2: try to map the frame the first time */
/* hint 1: seL4_ARCH_Page_Map()
* The *ARCH* versions of seL4 sys calls are abstractions over the architecture provided by libsel4utils
* this one is defined as:
* #define seL4_ARCH_Page_Map seL4_IA32_Page_Map
* in: https://github.com/seL4/libsel4utils/blob/master/include/sel4utils/mapping.h#L69
* The signature for the underlying function is:
* int seL4_IA32_Page_Map(seL4_IA32_Page service, seL4_IA32_PageDirectory pd, seL4_Word vaddr, seL4_CapRights rights, seL4_IA32_VMAttributes attr)
* @param service Capability to the page to map.
* @param pd Capability to the VSpace which will contain the mapping.
* @param vaddr Virtual address to map the page into.
* @param rights Rights for the mapping.
* @param attr VM Attributes for the mapping.
* @return 0 on success.
*
* Note: this function is generated during build. It is generated from the following definition:
* https://github.com/seL4/seL4/blob/master/libsel4/arch_include/x86/interfaces/sel4arch.xml#L52
* You can find out more about it in the API manual: http://sel4.systems/Info/Docs/seL4-manual.pdf
*
* hint 2: for the rights, use seL4_AllRights
* hint 3: for VM attributes use seL4_ARCH_Default_VMAttributes
*/
error = seL4_ARCH_Page_Map(ipc_frame_object.cptr, pd_cap, ipc_buffer_vaddr,
seL4_AllRights, seL4_ARCH_Default_VMAttributes);
if (error != 0) {
/* TODO 3: create a page table */
/* hint: vka_alloc_page_table()
* int vka_alloc_page_table(vka_t *vka, vka_object_t *result)
* @param vka Pointer to vka interface.
* @param result Structure for the PageTable object. This gets initialised.
* @return 0 on success
* https://github.com/seL4/libsel4vka/blob/master/include/vka/object.h#L178
*/
vka_object_t pt_object;
error = vka_alloc_page_table(&vka, &pt_object);
assert(error == 0);
/* TODO 4: map the page table */
/* hint 1: seL4_ARCH_PageTable_Map()
* The *ARCH* versions of seL4 sys calls are abstractions over the architecture provided by libsel4utils
* this one is defined as:
* #define seL4_ARCH_PageTable_Map seL4_IA32_PageTable_Map
* in: https://github.com/seL4/libsel4utils/blob/master/include/sel4utils/mapping.h#L73
* The signature for the underlying function is:
* int seL4_IA32_PageTable_Map(seL4_IA32_PageTable service, seL4_IA32_PageDirectory pd, seL4_Word vaddr, seL4_IA32_VMAttributes attr)
* @param service Capability to the page table to map.
* @param pd Capability to the VSpace which will contain the mapping.
* @param vaddr Virtual address to map the page table into.
* @param rights Rights for the mapping.
* @param attr VM Attributes for the mapping.
* @return 0 on success.
*
* Note: this function is generated during build. It is generated from the following definition:
* https://github.com/seL4/seL4/blob/master/libsel4/arch_include/x86/interfaces/sel4arch.xml#L37
* You can find out more about it in the API manual: http://sel4.systems/Info/Docs/seL4-manual.pdf
*
* hint 2: for VM attributes use seL4_ARCH_Default_VMAttributes
*/
error = seL4_ARCH_PageTable_Map(pt_object.cptr, pd_cap,
ipc_buffer_vaddr, seL4_ARCH_Default_VMAttributes);
assert(error == 0);
/* TODO 5: then map the frame in */
/* hint 1: use seL4_ARCH_Page_Map() as above
* hint 2: for the rights, use seL4_AllRights
* hint 3: for VM attributes use seL4_ARCH_Default_VMAttributes
*/
error = seL4_ARCH_Page_Map(ipc_frame_object.cptr, pd_cap,
ipc_buffer_vaddr, seL4_AllRights, seL4_ARCH_Default_VMAttributes);
assert(error == 0);
}
/* set the IPC buffer's virtual address in a field of the IPC buffer */
seL4_IPCBuffer *ipcbuf = (seL4_IPCBuffer*)ipc_buffer_vaddr;
ipcbuf->userData = ipc_buffer_vaddr;
/* TODO 6: create an endpoint */
/* hint: vka_alloc_endpoint()
* int vka_alloc_endpoint(vka_t *vka, vka_object_t *result)
* @param vka Pointer to vka interface.
* @param result Structure for the Endpoint object. This gets initialised.
* @return 0 on success
* https://github.com/seL4/libsel4vka/blob/master/include/vka/object.h#L94
*/
error = vka_alloc_endpoint(&vka, &ep_object);
assert(error == 0);
/* TODO 7: make a badged copy of it in our cspace. This copy will be used to send
* an IPC message to the original cap */
/* hint 1: vka_mint_object()
* int vka_mint_object(vka_t *vka, vka_object_t *object, cspacepath_t *result, seL4_CapRights rights, seL4_CapData_t badge)
* @param[in] vka The allocator for the cspace.
* @param[in] object Target object for cap minting.
* @param[out] result Allocated cspacepath.
* @param[in] rights The rights for the minted cap.
* @param[in] badge The badge for the minted cap.
* @return 0 on success
*
* https://github.com/seL4/libsel4vka/blob/master/include/vka/object_capops.h#L41
*
* hint 2: for the rights, use seL4_AllRights
* hint 3: for the badge use seL4_CapData_Badge_new()
* seL4_CapData_t CONST seL4_CapData_Badge_new(seL4_Uint32 Badge)
* @param[in] Badge The badge number to use
* @return A CapData structure containing the desired badge info
*
* seL4_CapData_t is generated during build.
* The type definition and generated field access functions are defined in a generated file:
* build/x86/pc99/libsel4/include/sel4/types_gen.h
* It is generated from the following definition:
* https://github.com/seL4/seL4/blob/master/libsel4/include/sel4/types.bf#L30
* You can find out more about it in the API manual: http://sel4.systems/Info/Docs/seL4-manual.pdf
*
* hint 4: for the badge use EP_BADGE
*/
error = vka_mint_object(&vka, &ep_object, &ep_cap_path, seL4_AllRights,
seL4_CapData_Badge_new(EP_BADGE));
assert(error == 0);
/* initialise the new TCB */
error = seL4_TCB_Configure(tcb_object.cptr, seL4_CapNull, seL4_MaxPrio,
cspace_cap, seL4_NilData, pd_cap, seL4_NilData,
ipc_buffer_vaddr, ipc_frame_object.cptr);
assert(error == 0);
/* give the new thread a name */
name_thread(tcb_object.cptr, "hello-3: thread_2");
/* set start up registers for the new thread */
seL4_UserContext regs = {0};
size_t regs_size = sizeof(seL4_UserContext) / sizeof(seL4_Word);
/* set instruction pointer where the thread shoud start running */
sel4utils_set_instruction_pointer(®s, (seL4_Word)thread_2);
/* check that stack is aligned correctly */
uintptr_t thread_2_stack_top = (uintptr_t)thread_2_stack + sizeof(thread_2_stack);
assert(thread_2_stack_top % (sizeof(seL4_Word) * 2) == 0);
/* set stack pointer for the new thread. remember the stack grows down */
sel4utils_set_stack_pointer(®s, thread_2_stack_top);
/* set the gs register for thread local storage */
regs.gs = IPCBUF_GDT_SELECTOR;
/* actually write the TCB registers. */
error = seL4_TCB_WriteRegisters(tcb_object.cptr, 0, 0, regs_size, ®s);
assert(error == 0);
/* start the new thread running */
error = seL4_TCB_Resume(tcb_object.cptr);
assert(error == 0);
/* we are done, say hello */
printf("main: hello world\n");
/*
* now send a message to the new thread, and wait for a reply
*/
seL4_Word msg;
seL4_MessageInfo_t tag;
/* TODO 8: set the data to send. We send it in the first message register */
/* hint 1: seL4_MessageInfo_new()
* seL4_MessageInfo_t CONST seL4_MessageInfo_new(seL4_Uint32 label, seL4_Uint32 capsUnwrapped, seL4_Uint32 extraCaps, seL4_Uint32 length)
* @param label The value of the label field
* @param capsUnwrapped The value of the capsUnwrapped field
* @param extraCaps The value of the extraCaps field
* @param length The number of message registers to send
* @return The seL4_MessageInfo_t containing the given values.
*
* seL4_MessageInfo_new() is generated during build. It can be found in:
* build/x86/pc99/libsel4/include/sel4/types_gen.h
* It is generated from the following definition:
* https://github.com/seL4/seL4/blob/master/libsel4/include/sel4/types.bf#L35
*
* hint 2: use 0 for the first 3 fields.
* hint 3: send only 1 message register of data
*
* hint 4: seL4_SetMR()
* void seL4_SetMR(int i, seL4_Word mr)
* @param i The message register to write
* @param mr The value of the message register
* https://github.com/seL4/seL4/blob/master/libsel4/arch_include/x86/sel4/arch/functions.h#L41
* You can find out more about message registers in the API manual: http://sel4.systems/Info/Docs/seL4-manual.pdf
*
* hint 5: send MSG_DATA
*/
tag = seL4_MessageInfo_new(0, 0, 0, 1);
seL4_SetMR(0, MSG_DATA);
/* TODO 9: send and wait for a reply. */
/* hint: seL4_Call()
* seL4_MessageInfo_t seL4_Call(seL4_CPtr dest, seL4_MessageInfo_t msgInfo)
* @param dest The capability to be invoked.
* @param msgInfo The messageinfo structure for the IPC. This specifies information about the message to send (such as the number of message registers to send).
* @return A seL4_MessageInfo_t structure. This is information about the repy message.
* https://github.com/seL4/seL4/blob/master/libsel4/arch_include/x86/sel4/arch/syscalls.h#L242
* You can find out more about it in the API manual: http://sel4.systems/Info/Docs/seL4-manual.pdf
*
* hint 2: seL4_MessageInfo_t is generated during build.
* The type definition and generated field access functions are defined in a generated file:
* build/x86/pc99/libsel4/include/sel4/types_gen.h
* It is generated from the following definition:
* https://github.com/seL4/seL4/blob/master/libsel4/include/sel4/types.bf#L35
* You can find out more about it in the API manual: http://sel4.systems/Info/Docs/seL4-manual.pdf
*/
tag = seL4_Call(ep_cap_path.capPtr, tag);
/* TODO 10: get the reply message */
/* hint: seL4_GetMR()
* seL4_Word seL4_GetMR(int i)
* @param i The message register to retreive
* @return The message register value
* https://github.com/seL4/seL4/blob/master/libsel4/arch_include/x86/sel4/arch/functions.h#L33
* You can find out more about message registers in the API manual: http://sel4.systems/Info/Docs/seL4-manual.pdf
*/
msg = seL4_GetMR(0);
/* check that we got the expected repy */
assert(seL4_MessageInfo_get_length(tag) == 1);
assert(msg == ~MSG_DATA);
printf("main: got a reply: %#x\n", msg);
return 0;
}
int main(void)
{
UNUSED int error;
/* give us a name: useful for debugging if the thread faults */
name_thread(seL4_CapInitThreadTCB, "hello-2");
/* get boot info */
info = seL4_GetBootInfo();
/* init simple */
simple_default_init_bootinfo(&simple, info);
/* print out bootinfo and other info about simple */
simple_print(&simple);
/* create an allocator */
allocman = bootstrap_use_current_simple(&simple, ALLOCATOR_STATIC_POOL_SIZE,
allocator_mem_pool);
assert(allocman);
/* create a vka (interface for interacting with the underlying allocator) */
allocman_make_vka(&vka, allocman);
/* get our cspace root cnode */
seL4_CPtr cspace_cap;
cspace_cap = simple_get_cnode(&simple);
/* get our vspace root page diretory */
seL4_CPtr pd_cap;
pd_cap = simple_get_pd(&simple);
/* create a new TCB */
vka_object_t tcb_object = {0};
error = vka_alloc_tcb(&vka, &tcb_object);
assert(error == 0);
/* initialise the new TCB */
error = seL4_TCB_Configure(tcb_object.cptr, seL4_CapNull, seL4_MaxPrio,
cspace_cap, seL4_NilData, pd_cap, seL4_NilData, 0, 0);
assert(error == 0);
/* give the new thread a name */
name_thread(tcb_object.cptr, "hello-2: thread_2");
/* set start up registers for the new thread: */
seL4_UserContext regs = {0};
/* set instruction pointer where the thread shoud start running */
sel4utils_set_instruction_pointer(®s, (seL4_Word)thread_2);
/* check that stack is aligned correctly */
uintptr_t thread_2_stack_top = (uintptr_t)thread_2_stack + sizeof(thread_2_stack);
assert(thread_2_stack_top % (sizeof(seL4_Word) * 2) == 0);
/* set stack pointer for the new thread. remember the stack grows down */
sel4utils_set_stack_pointer(®s, thread_2_stack_top);
/* actually write the TCB registers. we write 2 registers:
* instruction pointer is first, stack pointer is second. */
error = seL4_TCB_WriteRegisters(tcb_object.cptr, 0, 0, 2, ®s);
assert(error == 0);
/* start the new thread running */
error = seL4_TCB_Resume(tcb_object.cptr);
assert(error == 0);
/* we are done, say hello */
printf("main: hello world\n");
return 0;
}
static void restart_event(void *arg) {
restart_event_reg_callback(&restart_event, NULL);
seL4_UserContext context;
context.pc = restart_component;
seL4_TCB_WriteRegisters(restart_tcb, true, 0, 1, &context);
}
